Last week I went to a presentation at MIT made by a group of engineers that are half way through building a high technology barrier to protect Venice from rising waters. The project goes under the name MOSE (Moses).
Tourists in a rather damp Venice
Venice is a city built on an island situated in a lagoon that has been artificially shaped by human intervention over the last 500 years. The problem of rising sea levels and storms has meant that the city is regularly flooded, and so the project is to build a barrier spanning the three large openings to the lagoon so that it can be sealed in times of high tide and storms.
The flooding has been exacerbated by works carried out in the 1980’s and 90’s to build an industrial zone that involved the drainage of marshland areas, leading to a softening of the ground that made the city actually sink.
This is a 50 billion Euro project, and one of the biggest of its type ever attempted. A look at the data about the Thames Barrier (the first of its type) shows that the problem of high tides is getting worse. It was closed four times in the 1980s, 35 times in the 1990s, and 80 times since 2000, but why?
Strangely enough the problem is related to global temperature rise as we might imagine but not so much because of the melting of the icecaps. The fact is that water expands when it is heated so warming even by a couple of degrees has the effect of increasing its volume. The International Panel on Climate Change state that 70% of the presumed rise will be due to this factor.
So back to the barrier. The entire project is quite an undertaking as this YouTube video demonstrates. Years of planning followed by years of preparation, reclamation of marsh lands and sea defense construction not to mention the construction of an off shore oil terminal so that the ships no longer have to enter the lagoon. But Criticism is also rife.
Part of the finished engineering works on the MOSE project in Venice
Some engineers criticize the project on purely technical terms, other groups point to the lack of environmental impact study and others the cost.
This video also on YouTube tells a completely different story to the one above. Critics are arguing (amongst other things) that we do not know all of the variables involved (which seems to be true) and that the entire ecosystem of the lagoon will change.
I am no engineer so I cannot argue about the choices made, but I do have one simple question. With all of the movement of water involved in this project (serious high tides and the passage of thousands of liters of sea water a minute) would it not have been possible to build something that produced electricity instead of consuming it in huge amounts?
Details of how the flood defenses will work
The stakes are high as you might imagine, Venice is one of the most touristed cities in the world, but the high tides are flooding the monuments ever more regularly. We are talking about more than a meter of water, and footage on international TV of tourists walking on raised platforms through St Mark’s Square and fresco covered churches full of water does not go down well.
It is an old problem though, and one that is shared by many cities today. New Orleans is discussing a similar solution, and here in Boston the issue is also under debate.
They are all looking for a high technology solution to an age old problem that is getting steadily worse.
Producing electricity is often a dirty and polluting affair. Here in the US most is still produced by burning coal, rather like in the 19th century. Nuclear power production is seen by some as an answer as it doesn’t throw a tone of gasses and toxins into the atmosphere and can produce an enormous amount of power in comparison to the fuel it uses. But nuclear power brings its own sets of problems, you only have to look at recent events in Japan or take a trip to Ukraine to see that. And parts of the North Sea round the British Isles are contaminated from leaks from an infamous UK nuclear power station that shall remain nameless (although like New York it too was so good they named it twice) and the unforeseeable problems involved in storing radioactive waste for tens of thousands of years to name but a few rather thorny issues.
However some people that define themselves as fighting for a cleaner environmental electricity production policy, do argue that nuclear power is a move in the right direction, that alternative forms could never provide enough power to feed the planet and the very fact that nuclear power production does not create tons of carbon means it is advantageous in fighting the possible problems of global warming. There are undoubtedly advantages and disadvantages to this form of power production, but political and financial interests are also important factors to bear in mind.
There are several other ways of producing cleaner electricity though as we know, but they too have their problems. Building a dam to use the water to drive turbines can have devastating effects on the surrounding areas. Look at the Yangtze Dam project in China and the effect of this engineering project on the people and animals that used to inhabit the newly flooded areas.
Wind farms also seem a good solution but some people say they are ugly and here in Cape Cod in the US there is a large protest movement growing out of claims by people that live near wind turbines who claim health problems, stress and migraines due to the flickering effect of the blades turning in the sun.
Solar panels are always sold as a good option, but they are expensive to manufacture because processed silicon is costly due to its high demand. There are also the problems of how to dispose of the panel when it is no longer efficient and the nature of the silicon purification process.
In Italy farmers have taken government subsidies and covered their land with solar panels in a bid to improve profits. In some cases the panels form a sort of protection for the crops while they produce electricity, but in a lot of cases the agricultural land is just lost to a sea of silicon, causing people to complain both about the aesthetics and the land use issue. Government green incentives mean that there is no need to ask for planning permission so these ‘silicon farms’ as they are known are cropping up in some rather inopportune places (sorry, couldn’t resist the pun) and are in massive expansion as this article demonstrates.
But fortunately as we would hope in a blog like this there have been some really interesting developments recently in non silicon based solar energy production that we can look at.
Harnessing the sun
A couple of years ago researchers in Italy unveiled something called the Dye Solar Cell (DSC). It doesn’t use silicon to produce electricity but guess what? It uses vegetable dye from egg plant (aubergines). Well not being a scientist myself I thought, ‘yes, plants do photosynthesis don’t they, why didn’t I think of that?’, and I wasn’t far wrong.
The cells don’t have the same productive power so the area needs to be bigger to produce the same amount of power but they are incomparably cheaper and greener. Ideal for use for example on large low buildings such as barns or industrial units that can have the entire roof covered in vegetable cells and produce the electricity the occupants require for free. Good news.
But what if you haven’t got a huge roof? Well an Austrian company called Bleiner AG has developed a type of paint called Photon Inside that has the same capability. It has to be applied in a few coats and cost more than standard paint but a 50 square metre wall generates 3 Kw of electricity. It was developed for use on sailing boats so that they could operate a radio and radar while out at sea. Sorry but the only articles I can find online are in Italian.
Konarka is an interesting American company who have developed a power generating plastic. It can be made very thin and comes in a roll that you just cut to size, stick on your Venetian blinds or any other surface that takes a lot of sun and away you go. They also sell Power Fibre, as you would imagine it is a thread that you can weave, so you can make textiles that produce energy and can be made into clothes. I like this idea, you could buy a computer case that charges the computer using sunlight as you walk to work.
At the Massachusetts Institute of Technology (MIT) they have recently unveiled their ability to print solar panels on to paper. A great breakthrough as it makes the technology easy to transport and place in position but also cheap and hardwearing (you can laminate it). Research at the University of Verona in Italy goes one step further, they are developing completely transparent thin sheets of solar panels that you can attach to the window and look through.
These final applications described above really take solar electric production to a higher level, as practically any surface can be used to produce electricity. The breakthrough here is in the technology required to transport the current more than its production, as attaching the diodes has long been the most difficult part of thin surface electricity production as they tend to come off with any movement in the surface.
As Christopher pointed out in a recent post, global warming is a real and serious problem and electricity production could be a major element in pollutant gas production, but as I hope to have shown above there are many interesting developments if we allow ourselves a slightly different point of view on electricity management.
A less centralized way of thinking and we could produce a lot of the electricity we need in situ, using our own buildings as power plants.
I have written more extensively on this problem on the Bassetti Foundation website and there are also various related articles about renewable energy sources and the problems involved in their use.
Next week I will have a look at possible engineering solutions for the problematic issue of global warming.